Password Protect a PDF Online for Free

Payslips, contracts, medical reports, quotes: when a PDF contains data that must not end up in front of the wrong eyes, password protection is the simplest and most effective defense. The file stays openable everywhere — you just need to know the password.

With the free Protect PDF tool you add the protection in under a minute, straight from the browser, no account needed.

How to password protect a PDF in 3 steps

1. Open Protect PDF.
2. Upload your document (up to 20 MB).
3. Set a password and download the protected PDF.

From that moment on, anyone opening the file — in any PDF reader, on any device — will have to enter the password.

What protection is applied

The document is encrypted with 128-bit AES encryption, the PDF-standard protection supported by every modern reader (Adobe Reader, browsers, mobile apps). Without the password, the content is unreadable even when the file is opened with technical tools.

Tips for an effective password

• Use at least 10-12 characters, mixing letters, numbers and symbols.
• Avoid predictable data: no birth dates, names or "123456".
• Share the password through a different channel than the file: if you email the PDF, pass the password by phone or message.
• Don't reuse the same password for different documents sent to different people.

What if the password is no longer needed?

The reverse operation exists: Unlock PDF removes protection from a file whose password you already know — useful when you frequently edit or print a document you received protected. It is not a tool to bypass unknown passwords.

Privacy: what happens to the document

Both the uploaded file and the protected one are automatically deleted from the server within 60 minutes. No archive, no registration, no content analysis. For a complete clean-up before sending, you can also strip the author and hidden properties with Remove Metadata.

Frequently asked questions

Can the password be recovered if I forget it? No. That is exactly what encryption does: without the password the content is inaccessible. Store it in a password manager.

Can I protect multiple documents? Yes, with a free daily operation limit designed for normal use.

Does the protection also cover printing and copying? The password you set is the open password: it blocks access to the entire document, which is the strongest protection.

Related guides

Before protecting a document you may want to split it to extract only the pages worth sharing.